华北克拉通北缘中段中新元古代热-构造事件及其演化

近年华北地块北缘陆续发现和厘定出许多中新元古代变质火山-沉积地层,各种类型的深成侵入岩体以及各种样式的构造形迹,但对其性质及构造属性认识不统一.作者在详细研究前人成果基础上,认为华北地块北缘中段中新元古代经历了中元古代早期的伸展裂解、中元古代晚期的挤压汇聚、新元古代-早古生代的伸展裂解及早古生代晚期的挤压汇聚演化过程,伴随挤压汇聚有火山深成侵入岩浆活动和构造变质热事件的年代记录.中元古代晚期挤压汇聚事件表明华北地块北缘发育一条中元古代晚期大陆边缘碰撞造山带,这一碰撞造山事件为华北地块在Rodinia超大陆拼合模式提供了最基本的制约条件.

Hot-Tectonic Events and Evolution of North Margin of the North China Craton in Meso-Neoproterozoic

Up to date some studies proved that there are varieties of metamorphic sedimentary volcanic rocks, plutonic rocks and structural traces of Meso and Neoproterozoic along north margin of the North China craton. The tectonic history of Meso Neoproterozoic in the studied area could be summarized as follows: the extensional breaking in the early stage of the Meso Proterozoic, the compression convergencing in the late stage of the Meso Proterozoic, the extensional breaking in the early stage of the Neoproterozoic-Lower Paleozoic and the compression subducting in the late stage of the Lower Paleozoic.They are identified four stages representing the Meso and Neoproterozoic Paleozoic hot tectonical events and the ages obtained by analyzing the rock samples from north margin of the North China craton. The orogenic belt in late stage of the Meso Proterozoic along north margin of the North China craton, mainly consists of ophiolite relics of Kaiyuan rock group, island arc volcanic rocks of Weijiagou and Bainaimiao groups, and S type granites in the late stage of the Meso Proterozoic. The orogenic belt in late stage of the Meso Proterozoic along north margin of the North China craton related to other Meso Proterocoic orogenic belts on cratons of the world will provide important constraints for reconstructing the Rodinia super continent.